biology essay

The Components Of Soap Biology Essay

Published: 23, March 2015

This essay has been submitted by a student. This is not an example of the work written by our professional essay writers.

In this fast growing world, before doing only thing it is really important to know about that particular thing in details. For examples, if I want to buy soap, first I need to know as what substance and chemicals are used in this particular soap. Then we check the manufacture date and then expire date.

Soaps and detergent, thought it is used for some reason but they two are completely it is used for some reason but they two are completely different from each other. We can say that the main components of soap are fatty acid, oils and fats, and alkali where as detergent's main component are alkalis, different types of chemicals etc. Though it is used for the same reason, the way it is used is also different and the way they are made is also different from each other.

We wear different colours of clothes but do we really care as how this colours are extracted so it is also important to learn as how these natural dyes are extracted and how it is used for making beautiful colours for clothes etcâ€¦ There are many plants which grow at different places with different climatic conditions. The extraction of essentials oils from different plants with different historical is also important because it is directly connected to our daily life.

So in general, all these substance mentioned above i.e. soap, detergent, natural dyes, essential oils and beverage are all important fact that has direct or indirect connection with our daily life so we should be able to analyse as how to use this things in right quantity.

Soap

Definition

Soap, technically, is defined as: the alkali salt of a fatty acid. It is the product that results from the reaction of a fatty acid and a strong base (alkali). In cleansing soaps, the fatty acids come from oils and fats; the strong alkali base is sodium hydroxide, also known as "lye", (for hard soaps) or potassium hydroxide, also known as "potash", (for soft soaps).

Later, the ancient Romans discovered the cleaning power of soap accidentally.Â At Mount Soap, where animals were sacrificed, rain mixed animal fats, wood ashes and clay in to the soil.Â Incidentally, women washing their clothes by the stream found it was much easier to wash their clothes with some of this clay mixture. Legend links Mount Saop with the process of soap making (soapnification). Interestingly, although Romans are famous for their baths, they actually did not use soap to wash. They coated themselves in oils and then used a scraping tool called a stingily to clean their bodies.Â However, bars of soap were found in the ruins of Pompeii and archaeologists believe soap was used for laundry and occasionally on the body. http://www.algebralab.org/img/39815402-e6a9-4c86-ab6f-925caf118b71.gif

The Components of Soap

In order to understand the chemistry of soap, it is first necessary to take a look at the chemistry of the component parts.

Fatty Acids

A fatty acid is made up of a long chain of hydrogen and carbon atoms, with an extra hydrogen atom at one end and a special group of atoms called a "carboxyl group" (made up of two oxygen, one hydrogen and one carbon atom) on the other end.

palmitic acid diagram

A fatty acid can be "saturated" or "unsaturated". In a saturated fatty acid, the carbon atoms are bonded with single bonds; they share one set of electrons. As a result, saturated fatty acids have two hydrogen atoms for each carbon atom. Palmitic Acid, pictured above, is a saturated fatty acid.

In an unsaturated fatty acid, there is at least one double bond where one set of carbon atoms is bonded by sharing two sets of electrons, instead of each being connected to a hydrogen atom. Oleic Acid, below, is an unsaturated fatty acid.

oleic acid diagram

Fatty acids are found in fats and oils.

Oils and Fats

There is no sharp distinction between a fat and oil. "Oil" commonly means a liquid which at ordinary temperature will flow as a slippery, lubricating, fairly thick fluid. "Fat" normally implies a greasy, solid substance slippery to the touch. It is necessary to differentiate the oils and fats used in the manufacture of soap.

Hydrocarbon (petroleum-based) oils or paraffin's, while included in the general term "oil," do not contain fatty acids and cannot be used to make traditional soap. Animal- and vegetable-based oils and fats do contain the necessary fatty acids, in the form of triglycerides.

Triglycerides

When the carboxyl group ends of three fatty acid molecules combine with one molecule of glycerol it produces a triglyceride.

triglyceride diagram

This is what we usually think of as "oil" or "fat". The actual physical characteristics of the oil depend upon which fatty acids have attached to the glycerol and whether they are connected to the top, middle or bottom of the glycerol molecule. If primarily unsaturated fatty acids are contained in the triglyceride, then the oil is considered to be an "unsaturated fat". The type of fatty acids also determines whether the triglyceride is solid or liquid at room temperature, how thick it is the nutritional value and - for soap makers - the qualities the oil will impart to the soap and its lather.

Fats & Oils

It seems that every week brings new reports of the effects of dietary fats and oils on health. Many of these reports indicate that a diet high in fat is unhealthy, leading to heart disease and circulatory problems. As a result, grocery shelves are filled with food packages that proclaim their contents to be "low fat" or "fat free." However, other reports caution that dietary fats are necessary for health, and that the chemical nature of the fats is important. We are admonished to be concerned about saturated versus unsaturated fats, to avoid the former and consume the latter. Furthermore, with regard to unsaturated fats, we need to be concerned whether they are "trans" fats. The terminology applied to fats is based on the chemical structure of their zolecules. Fats and oils belong to a group of biological substances called lipids. Lipids are biological chemicals that do not dissolve in water. They serve a variety of functions in organisms, such as regulatory messengers (hormones), structural components of membranes, and as energy storehouses. Fats and oils generally function in the latter capacity. Fats differ from oils only in that they are solid at room temperature, while oils are liquid. Fats and oils share a common molecular structure, which is represented by the formula below.

This structural formula shows that fats and oils contain three ester functional groups. Fats and oils are esters of the tri-alcohol, glycerol (or glycerine). Therefore, fats and oils are commonly called triglycerides, although a more accurate name is triacylglycerols. One of the reactions of triglycerides is hydrolysis of the ester groups.

This hydrolysis reaction produces glycerol and fatty acids, which are carboxylic acids derived from fats and oils. In the fatty acids, Ra, Rb, and Rc, represent groups of carbon and hydrogen atoms in which the carbon atoms are attached to each other in an unbranched chain.

The hydrolysis reaction is promoted by acids and by bases. When a strong base such as NaOH (lye) is used, the product contains salts of the fatty acids. These salts of fatty acids are the functional ingredient in soap. The ingredients lists of some soaps include sodium tallowate, a generic name for the mixture of fatty acid salts obtained from tallow (animal fat), and sodium cocoate, obtained from coconut oil.

Triglyceride molecules contain mostly carbon and hydrogen atoms, with only six oxygen atoms per molecule. This means that fats and oils are highly reduced (that is, un-oxidized). They are, in this way, similar to the hydrocarbons in petroleum, and like petroleum they are good fuels. The main biological function of triglycerides is as a fuel. The normal human body stores sufficient energy in fat for several weeks' survival. This storage ability helps the organism deal with unpredictable variations in the food supply. Plants, too, store energy in fats and oils. Oils are particularly common in seeds, where the stored energy helps seedlings during germination, until they can exploit solar energy through photosynthesis.

Fatty acids contain an even number of carbon atoms, from 4 to 36, bonded in an unbranched chain. Most of the bonds between carbon atoms are single bonds. If all of these bonds are single bonds, the fatty acid is said to be saturated, because the number of atoms attached to each carbon atom is the maximum of four. If some of the bonds between carbon atoms are double bonds, then the fatty acid is unsaturated. When there is only one double bond, it is usually between the 9th and 10th carbon atom in the chain, where the carbon atom attached

to the oxygen atoms is counted as the first carbon atom. If there is a second double bond, it usually occurs between the 12th and 13th carbon atoms, while a third is usually between the 15th and 16th.

Double bonds between carbon atoms in fatty acids can cause kinks in the chains of atoms. This is particularly true for cis double bonds. These kinks prevent the molecules from stacking together well. Because they do not fit together well, unsaturated fatty acids and triglycerides have lower melting points than saturated ones. Thus fats, which are solids, are usually more saturated than oils, which are liquids at room temperature.

Highly unsaturated oils undergo a chemical reaction in the presence of oxygen and light. In this reaction the unsaturated carbon atoms become saturated by reaction with oxygen. This reaction causes separate molecules of oil to become linked by oxygen atoms. Linking from molecule to molecule causes the oil to solidify. Oils that undergo this process are called drying oils and are used in oil paints. Oils that are rich in double bonds are most able to undergo this process. Among the most unsaturated of vegetable oils is linseed oil, the preferred medium for artists' oil paint

Alkali

An alkali is a soluble salt of an alkali metal like sodium or potassium originally, the alkalis used in soap making were obtained from the ashes of plants, but they are now made commercially. Today, the term alkali describes substance that chemically is a base (the opposite of an acid) and that reacts with and neutralizes an acid. The common alkalis used in soapmaking are sodium hydroxide (NAOH), also called caurtic sada, and potassium hydroxide (KOH), also called caurtic potash.

How Soaps are made

To make soap, the first step is to start with fats and oils (obtained from plants or animals) that are reduced to fatty acids and glycerine with a high pressure steam. The fatty acids then combine with either sodium or potassium salts (an alkali or base) to produce soap and water. This is exactly what happened when our early American settlers combined ashes, containing lye, a base, with animal fats.

After this process, the soap possesses a hydrophilic end that is attracted to water and a hydrophobic end that is repelled by water, allowing the soap to break down materials that dissolve in both oil and water. Sodium soaps are harder and appear as bar soaps, while the potassium soaps are softer and are used in liquid hand soaps and shaving creams.

Fatty acids consist of the elements carbon (C), hydrogen (H) and oxygen (O) arranged as a carbon chain skeleton with a carboxyl group (-COOH) at one end. Saturated fatty acids (SFAs) have all the hydrogen that the carbon atoms can hold, and therefore, have no double bonds between the carbons. Monounsaturated fatty acids (MUFAs) have only one double bond. Polyunsaturated fatty acids (PUFAs) have more than one double bond.

Butyric AcidÂ Â Â Butyric Acid

Butyric acid (butanoic acid) is one of the saturated short-chain fatty acids responsible for the characteristic flavor of butter. This image is a detailed structural formula explicitly showing four bonds for every carbon atom and can also be represented as the equivalent line formulas:

CH3CH2CH2COOH or CH3(CH2)2COOH

The numbers at the beginning of the scientific names indicate the locations of the double bonds. By convention, the carbon of the carboxyl group is carbon number one. Greek numeric prefixes such as di, tri, tetra, penta, hexa, etc., are used as multipliers and to describe the length of carbon chains containing more than four atoms. Thus, "9,12-octadecadienoic acid" indicates that there is an 18-carbon chain (octa deca) with two double bonds (di en) located at carbons 9 and 12, with carbon 1 constituting a carboxyl group (oic acid). The structural formula corresponds to:

CH3CH2CH2CH2CH2CH=CHCH2CH=CHCH2CH2CH2CH2CH2CH2CH2COOH

9,12-octadecadienoic acid Â (Linoleic Acid)

which would be abbreviated as:

CH3(CH2)4CH=CHCH2CH=CH(CH2)7COOH

Fatty acids are frequently represented by a notation such as C18:2 that indicate that the fatty acid consists of an 18-carbon chain and 2 double bonds. Although this could refer to any of several possible fatty acid isomers with this chemical composition, it implies the naturally-occurring fatty acid with these characteristics, i.e., linoleic acid.Â Double bonds are said to be "conjugated" when they are separated from each other by one single bond, e.g., (-CH=CH-CH=CH-). The term "conjugated linoleic acid" (CLA) refers to several C18:2 linoleic acid variants such as 9,11-CLA and 10,12-CLA which correspond to 9,11-octadecadienoic acid and 10,12-octadecadienoic acid. The principal dietary isomer of CLA is cis-9,trans-11Â CLA, also known as rumenic acid. CLA is found naturally in meats, eggs, cheese, milk and yogurt.

CH3(CH2)5CH=CH-CH=CH(CH2)7COOH

9,11-Conjugated Linoleic Acid

How water hardness affects cleaning action?

Although soap is a god cleaning agent, its effectiveness is reduced when used in hard water. Harness in water is caused by the presence of mineral salts - mostly those of calcium (Ca) and magnesium (Mg), but sometimes also iron (Fe) and maganese (Mn). The mineral salts react with soap to form an insoluble precipitate known as film or scum.

Soap film does not rinse away easily. It tends to remain behind and produces visible deposit on clothing and makes fabrics feel stiff. It also attaches to the insides of that tubs, sinks and washing machines. Some soap is used up by reacting with hard water minerals to form the film. This reduces the amount of soap available for cleaning. Even when clothes are washed in soft water, some hardness minerals are introduced by the soil and cloths. Soaps molecules are not very versatile and cannot be adapted to today's Varity of fibbers, washing temperatures and water conditions.

Types of Soap

Herbal Soap

The best way to use herbs in soap is to add dry, finely powdered herbs to the fat before adding the lye/water. Use anywhere from 1 tablespoon to 1/4 cup dried herbs to 1 1b soap. Restrict coarsely ground herbs to about 1 to 2 tablespoons per 1b soap because they contribute coarseness to the soap that sometimes makes it uncomfortable during use.

The nicest way to add properties of herbs to soap is the addition of pure essential oils. Over time, soap can develop a "lye - fat" odor, which essential oil prevents. Use anywhere from 1 teaspoon to 2 tablespoons essential oil per 1b soap (depending on the strength of the oil) colour is an illusive thing as far as soap is concerned. Natural colours can be obtained by adding 2 tablespoons red clay, calendula petals or yellow palm oil.

To super fat with other fats, you can subtract about 2 weight lye from on 1b batches of soap recipes which allows excess fat to remain.

There are three ways to deal with soda ash: -

Try to prevent it

Immediately after pouring soap into moulds, cover the soap with plastic wrap or waxed paper. Press the wrap or paper onto the surface of the soap to prevent air contact.

Cut it away.

Overfill the moulds slightly. Later, when the sopa hardens take a knife and cut the soap level with the moulds. This also cuts away the soda ash.

Wash it away.

Wait until the soap ages and hardens. Wash the powder away by rubbing the soap with your hands under running water or by rubbing the soap over a wet dishcloth. Set the soap aside to dry then enjoy soap.

Petrochemicals and oleochemicals

Like the fatty acids used in soapmaking, both petroleum and fats and oils contain hydrocarbon chains that are repelled by water but attracted to oil and grease in soils. These hydrocarbon chain sources are used to make the water- hating end of the surfactant molecule. Other chemicals, such as sulphur trioxide, sulphuric acid and ethylene oxide, are used to produce the water - loving end of the surfactant molecule.

Detergents

A detergent is an effective cleaning product because it contains one or more surfactants. Because of their chemical makeup, the surfactants used in detergents can be engineered to perform well under a variety of conditions. Such surfactants are less sensitive than soap to the hardness minerals in water and most will not form a film.

Detergent surfactants were developed in response to a shortage of animal and vegetable fats and oils during World War I and World War II. In addition, a substance that was resistant to hard water was needed to make cleaning more effective. At that time, petroleum was found to be a plentiful source for the manufacture of these surfactants. Today, detergent surfactants are made from a variety of petrochemicals (derived from petroleum) and olechemicals (derived from fats and oils).

Other chemicals

Chemicals, such as sulphur trioxide, sulphuric acid and ethylene oxide, are used to produce water loving end of the surfactant molecules.

Detergents are amphipathic molecules that possess both a hydrophobic (water-fear) and a hydrophilic (water-friend) group that allow them to act as excellent solubilization agents.

Hydrophobicity

Hydrophobicity from the Greek words hydro (water) and phobos (fear) refers to the physical property of a molecule (known as a hydrophobe) that is repelled from a mass of water. Water molecules form a highly ordered structure by the intermolecular action of its hydrogen bonds. Polar, or hydrophilic, molecules can readily dissolve in water as their charged groups can interact with the hydrogen bonds maintaining a ordered structure.

Non-polar, or hydrophobic, molecules are unable to form stable structures and are repelled by the water molecules and are therefore immiscible with the water. The addition of hydrophobic molecules disrupts the energy favoured structure of water, creating "holes" devoid of water molecules. The water molecules at the edge of the holes rearrange into an ordered manner and this results in an unfavorable decrease in entropy. To combat the loss of entropy, water molecules force the hydrophobic molecules to cluster to occupy the smallest space possible. This effect is known as the hydrophobic effect.

The hydrophobic effect plays an important role in protein structure and is involved in defining the tertiary structure of proteins. The amino acids of proteins can be polar or non-polar and therefore in an aqueous environment the proteins fold to protect the hydrophobic non-polar groups from the water molecule.

How do detergents work?

The structure of detergents is keys to its ability to function as a solubilization agent. Detergent molecules contain a polar head group from which extends a long hydrophobic carbon tail (Figure 1).

The amphipathic properties of the detergent molecules allows them to exhibit unique properties in aqueous solutions. The polar (hydrophilic) head groups interact with the hydrogen bonds of the water molecules and the hydrophobic tails aggregate resulting in highly organized spherical structures called micelles (Figure 2). At low concentrations, the detergents exist as single molecules or small aggregates and as the concentration increases micelles begin to form. The concentration at which micelles begin to form is known as the Critical Micelle Concentration (CMC).

Figure 2: A detergent micelle formed with SDS molecules in an aqueous solution (left) or a non-aqueous solution (right).

A wide range of detergents are routinely used to release, or solubilize, proteins from lipid membranes.

Biological membranes consist of phospholipids that are similar to detergents as they have the same amphipathic properties. The phospholipids have a charged polar head normally connected to two hydrophobic groups or tails. The phospholipids assemble as bilayers , with the hydrophobic tails between two faces of polar head groups.

For biological membranes, proteins and lipids (i.e. cholesterol) are embedded in the bilayer forming the fluid mosaic model. The proteins are held in the lipid bilayer by hydrophobic interactions between the lipid tails and hydrophobic protein domains. These integral membrane proteins are not soluble in aqueous solutions as they aggregate to protect their hydrophobic domains, but are soluble in detergent solutions.

The proteins are released from lipid bilayers by detergents as the detergent micelles have similar properties as the lipid bilayer. The integral membrane proteins embed themselves in the detergent micelles protecting their hydrophobic domains from aggregation.

Critical Micelle Concentration (CMC)

The solubilization of proteins from lipid bilayers is dependent on the Critical Micelle Concentration (CMC) of the detergents.

The CMC is defined as the concentration of surfactants (detergents) above which micelles are spontaneously formed. The CMC is dependent on the alkyl chain length, presence of double bonds, branched points and additives in the solubilization buffers. As the alkyl chains increase, the CMC decreases; the introduction of double bonds and branch points increases the CMC; additives, such as urea, that are chaotropic increase the CMC.

The detergent CMC is important as it allows researchers to use the precise amount of detergent, too little means inadequate solubilization of proteins (Figure 5), too much can affect downstream process and problematic detergent removal steps.

CMC can be determined by light scattering (increases with detergent concentration), surface tension (decrease) and dye solubilization (increase) (Vulliez-Le Normand and Jean-Luc Eisele (1993)). All three techniques are time consuming and are rarely performed for this reason. G-Biosciences has developed Optimizer-blueBALLSâ„¢, which is based on the dye solubilization method, but is significantly more convenient.

Optimizer-blueBALLSâ„¢ are simple and comparable to CMC determined by expensive light scattering or surface tension methods. Furthermore, this method is applicable to all detergents, including steroid based detergents such as CHAPS and deoxycholate, as well as non-steroid detergents like Î²-octylglucoside.

Optimizer-blueBALLSâ„¢ are hydrophobic blue dye coated glass balls that behave as membrane proteins. Simply add to your extraction, or perform parallel extractions to ensure complete solubilization. They ensure that only the minimal amount of detergent is used for maximum extraction, resulting in improved downstream processing results.

Essential Oils

An essential oil is a concentrated, hydrophobic liquid containing volatile aroma compounds from plants. Essential oils are also known as volatile, ethereal oils or aetherolea, or simply as the "oil of" the plant from which they were extracted, such as oil of clove. An oil is "essential" in the sense that it carries a distinctive scent, or essence, of the plant. Essential oils do not as a group need to have any specific chemical properties in common, beyond conveying characteristic fragrances.

Essential oils are generally extracted by distillation. Other processes include expression, or solvent extraction. They are used in perfumes, cosmetics, soap and other products, for flavoring food and drink, and for scenting incense and household cleaning products.

Various essential oils have been used medicinally at different periods in history. Medical application proposed by those who sell medicinal oils range from skin treatments to remedies for cancer, and are often based on historical use of these oils for these purposes. Such claims are now subject to regulation in most countries, and have grown vaguer to stay within these regulations.

Interest in essential oils has revived in recent decades with the popularity of aromatherapy, a branch of alternative medicine which claims that the specific aromas carried by essential oils have curative effects. Oils are volatilized or diluted in carrier oil and used in massage, diffused in the air by a nebulizer or by heating over a candle flame, or burned as incense, for example.

The techniques and methods first used to produce Ethereal oil (Essential oil) was first mentioned by Ibn al-Baitar (1188-1248), an Andalusian physician, pharmacist and chemist.

How to Make Essential Oils

Essential oils are highly concentrated, volatile oils that can be extracted from aromatic plants. Their use dates back to ancient times, and their wide variety of therapeutic, medicinal and culinary uses has ensured their continued popularity. About 700 different kinds of plants contain useful essential oils, and there are several methods employed to extract them, the most common of which is distillation. While essential oils can be very expensive to buy, they are relatively cheap to distill at home. This guide provides basic instructions on how to extract the oils using the relatively simple and effective water-and-steam distillation process.

What Are Essential Oils?

Essential oils are highly concentrated natural plant extracts; a drop or two can produce significant results. An entire plant, when distilled, might produce only a single drop of essential oil. That is why their potency is far greater than dried herbs. Pressing or distillation extracts the subtle, volatile liquids (meaning they evaporate quickly) from plants, shrubs, flowers, trees, roots, bushes, and seeds, that make up essential oils.

Essential oils are the life-blood of the plant, protecting it from bacterial and viral infections, cleansing breaks in its tissue and delivering oxygen and nutrients into the cells. In essence, they act as the immune system of the plant. That is why they are so essential to the plant without them, plants could not survive.

In the human body, they have a similar action -- such as transporting valuable nutrients to the cells; increasing oxygen intake, and digesting toxic waste in the blood. This is because the three primary elements - carbon, hydrogen and oxygen-are common to both human beings and essential oils. This shared chemistry makes essential oils one of the most compatible of all plant substances with human biochemistry.

Not only that, but the lipid-soluble structure of essential oils and the fact that they have a protein-like structure similar to human cells and tissues makes them even more compatible with human tissue.

Essential oils are very different from vegetable oils (also called fatty oils), such as corn oil, olive oil, peanut oil, etc. Fatty oils are produced by pressing nuts or seeds. They are quite greasy, are not antimicrobial nor help transport oxygen, and will go rancid over time. Essential oils, however, are not greasy nor do they clog the pores like vegetable oils can.

Essential oils are highly complex substances. They are mosaics of hundreds - even thousands - of different natural chemicals. The average essential oil may contain anywhere from 80 to 400 known chemical constituents. Many oils contain even more, occurring in minute quantities - but all contributing to the oil's therapeutic effects. It requires years of study to understand these constituents, their activity and functions.

Different varieties of the same oil can have widely different therapeutic actions, depending on their chemistry. For example, basil high in linalool or fenchol is primarily used for its antiseptic properties. However, basil high in methyl chavicol is more anti-inflammatory than antiseptic. A third type, basil high in eugenol, has both anti-inflammatory and antiseptic effects.

In addition, essential oils can be processed in different ways, which dramatically effects their chemistry and medicinal action. Oils that have been redistilled two or three times are obviously not as potent as oils that have been distilled only once. Also, oils that are subjected to high heat and pressure in processing have an inferior profile of chemical constituents, since excessive heat and temperature fractures and breaks down many of the delicate aromatic compounds within the oil -- compounds that are responsible for much of the therapeutic action of the oil.

Of even greater importance is the fact that some oils are thinned or cut (i.e. adulterated) with synthetic chemicals.

The Different Types of Essential Oils

Essential oils are obtained by different methods distillation being the most familiar. There are four types of essential oils:

1. Absolutes vs. concretes

2. Expressed

3. Solvent-extracted

4. Steam-distilled

Absolutes are "essences," rather than "essential" oils. They are generally obtained from the extraction of a concrete with alcohol. A concrete is the solid waxy residue derived from hexane extraction of plant material (usually the flower petals).

This method of extraction is used for botanicals where the fragrance and therapeutic parts of the plant can only be unlocked using solvents. These are not to be used internally, as traces of petrochemicals remain in the oil. Jasmine and neroli are examples of absolutes.

Expressed oils are pressed from the rind of fruits (usually citrus). Tangerines, grapefruits, lemons and oranges are produced by this method. Technically speaking, these are not "essential oils" - they are expressed oils, but they are highly regarded for their therapeutic properties, none the less. It is best to use only organically grown crops for this method, since pesticide residues, especially highly toxic, oil-soluble carbonate and chloride-based petrochemicals, can become highly concentrated in the oil.

Solvent extraction involves the use of oil-soluble solvents, such as hexane, dimethylenechloride, and acetone. There is no guarantee that the finished product will be free of solvent residues.

Steam distillation is the oldest and most traditional method of extraction. Plant material is inserted into a cooking chamber, and steam is passed through it. After the steam is collected and condensed, it is processed through a separator to collect the oil. The amount of pressure used, the amount of time the plant material is steamed and the material the steam chamber is constructed of contribute a great deal to the quality of the oil (or lack of).

How Essential Oils Are Used

Historically, there have been three models for using essential oils: the French, the German, and the English methods.

The English traditionally dilute a small amount of essential oil in vegetable oil and massage the body to relax and relieve stress.

The French prefer to ingest (swallow) therapeutic-grade essential oils. Many French practitioners have found that taking the oils internally is highly effective.

The Germans recommend inhalation of the essential oils. There is good reason for this - research has shown that these aromatic compounds can exert strong effects on the brain, especially on the hypothalamus (the hormone command center of the body) and the limbic system (the seat of emotions). Some essential oils can dramatically increase oxygenation and activity in the brain. Oils also increase ozone and negative ions, which inhibit bacterial growth. Essential oils can make chemicals non-toxic by fracturing their molecular structure. European scientists have found that essential oils work as natural chelators, bonding to metallics and chemicals and carrying them out of the body. Diffused essential oils make outstanding air filtration systems, helping to remove dust particles from the air and destroying odors from mold, cigarettes, animals, etc.

When diffused, the oils reach the brain by means of the olfactory system. The olfactory membranes have about 800 million nerve endings that receive micro-fine, vaporized oil particles. They carry them along the axon of the nerve fibers and connect them with the secondary neurons in the olfactory bulb. The impulses are then transported to the limbic system and the olfactory sensory center at the base of the brain. Then they pass between the pituitary and pineal gland and move to the amygdala - the memory center. The impulses than travel to the gustatory center where the sensation of taste is perceived.

The best method of application depends on the need. In some cases, inhalation might be preferred over topical application if the goal is to induce weight loss or balance mood and emotions. In other cases, topical application would produce better results, as in the case of muscle or spinal injuries. For indigestion, peppermint oil taken orally is very effective. Yet peppermint can also produce the same results when massaged on the stomach. In some cases, all three methods of application (topical, inhalation and ingestion) are interchangeable and may produce similar benefits.

The two most common methods of essential oil application are cold-air diffusing and neat (undiluted) topical application. Healing response is greatly enhanced when essential oils are incorporating into the disciplines of reflexology, Vita Flex, acupressure, acupuncture, auricular techniques, lymphatic massage, spinal touch, and the Raindrop Technique.

Essential Oil Extraction Process- Distillation

Steam Distillation

The majority of essential oils available today are extracted using a steam distillation process. It's the oldest form of essential oil extraction and is believed by many to be the only way oils should be extracted. The process really is quite simple and as long as this extraction process is closely monitored, the steam will remain at a temperature that won't damage the plants.

The desired plant material is placed onto a still. A still is a specialized piece of equipment that is used in the distillation process. It consists of a vessel into which heat is added and a device that is used for cooling. The plant is first placed into the vessel. Next steam is added and passed through the plant. The heat from the steam helps to open the pockets of the plant that contain the plant's aromatic molecules or oils. Once open, the plant releases these aromatic molecules and in this state, the fragrant molecules are able to rise along with the steam.

The vapors carrying these molecules travel within a closed system towards the cooling device. Cold water is used to cool the vapors. As they cool, they condense and transform into a liquid state. The liquid is collected in a container and as with any type of oil/water mixture, it separates. The oils float towards the top while the water settles below. From there, it's a simple matter of removing the oils that have been separated.

These are the highly condensed, aromatic oils used in aromatherapy.The water is not discarded, however. The water, which also contains the plant's aroma along with the other parts of the plant that are water soluble, are the hydrosols - a milder form of the essential oils. These, too are also used in aromatherapy. When steam is used; it's created at a pressure higher than that of the atmosphere. The boiling point is above 100 degrees Celsius and creates an extraction process that is safe and fast. If the temperature is allowed to become too hot, however, the plant material as well as its essential oils can easily become damaged.

Water Distillation

Water distillation involves placing the desired plant material in a still and then submerging it in water. The water is then brought to a boil. The heat helps open the pockets containing the plant's aromatic molecules so they can be extracted. The vapors cool and condense the essential oils separate from the water and they're collected.

The water in this case provides protection for the plant because it acts as a barrier. Less pressure is used as well as a lower temperature than that which is used in the steam distillation method. This extraction method works well with plants that cannot tolerate high heat.

Other distillation methods

Hydro distillation is similar to steam distillation. The only difference is that instead of introducing the heat from the bottom and up through the still, as happens in steam distillation, the heat passes into the still from the top. It's cooled from below, which makes collection of the essential oils easier. This method actually results in a higher yield of essential oils because less steam and consequently less processing time are involved.

In a water/steam combination distillation method, plant material is submerged into heated water and steam is forced through the water, opening the pockets containing the aroma molecules. When cooled, the essential oils condense and are collected as described above.

Essential Oil Extraction Process- Expression

It's true that essential oils are an essential part of aromatherapy. But contrary to what some people think, the term 'essential' doesn't mean essential as in 'being a necessary part of'. Instead, essential oils are the oils extracted from the 'essence' of a plant - those parts that contain the plant's aroma molecules.

Using different methods of extraction guarantees that the highest concentrations of oils can be extracted. Essential oils are gathered from many different types of plants and many different parts of those plants. Flowers, fruits, herbs, stems, roots, leaves, buds, blossoms, seeds, nuts and even tree bark produce some of the most aromatic and therapeutic essential oils. Essential oil extraction methods fall under three main categories: expression, solvent extraction and distillation. The following is an overview of these extraction processes and methods.

Expression

The expression form of essential oil extraction does not involve the use of a heat source. This is the method commonly used to extract oils from the rinds of citrus. In earlier times, rinds were squeezed by hand and a sponge was used to collect the essential oils. The fruit would be removed and then the rinds along with the pith would be soaked in water to make them easier to work with. They'd then be turned upside-down. Turning them upside-down caused the cells containing the oils to break apart. Once broken, the oils would drip out and soak into a nearby sponge. When the sponge became saturated, the oils were squeezed into a container so they could be decanted.

Machine Abrasion

Those were quite laborious processes, and thankfully, technological advances led to the invention of machines to do this type of tedious work. Nowadays, oils from rinds are extracted using centrifugal force. This rapid process is called Machine Abrasion.

Cold Pressed

This form of expression extraction is also used to extract essential oils from nuts and seeds and from the rinds of citrus. Mechanical pressure is used to force the oils out. The oils extracted contain water, but this water will, in time, evaporate, leaving just the essential oils. The downside of using this extraction method is that the cold pressed oils spoil more quickly than those extracted using other methods. That's why, to eliminate waste, it's important to purchase these essential oils in small quantities.

Natural Dyes

There are two different types of natural dyes: substantive and adjective. A substantive dye is one that will colour the fibre without the use of a mordant e.g. indigo. The use of a mordant with a substantive dye extends their colour potential and increases their fastness.

An adjective dye requires the use of mordants to intensify colour and to make them permanent. The majority of natural dyes an adjective. It should be noted that all natural dyes can be used in the absence of mordants although wash, light and rub fastness are very low and colour potential is limited.

Dye extracts are always stronger than dye liquors or raw materials. This is because the dye has already been extracted from the raw material. If using extracts adjust the amount used.

About Natural Dyes

Contrary to popular opinion, natural dyes are often neither safer nor more ecologically sound than synthetic dyes. They are less permanent, more difficult to apply, wash out more easily, and often involve the use of highly toxic mordants. Some natural dyes, such as the hematein derived from logwood, are themselves significantly poisonous. Of course, the color possibilities are far more limited; the color of any natural dye may be easily copied by mixing synthetic dyes, but many other colors are not easily obtained with natural dyes. However, some mordant are not very toxic, and the idea of natural dyestuffs is aesthetically pleasing.

Fiber choice for natural dyeing

Wool is generally the best fiber to color with natural dyes. It will attach to a wider variety of dye chemicals than cellulose fibers such as cotton, and, since it is usually washed in cool water, or only dry-cleaned, the relative impermanence of most natural dyes is less of an issue.

Cotton is less suitable for many natural dyes. As a rule, science fair projects involving natural dyes should be done using wool yarn or fabric, not cotton (though comparing the same dye on the two different types of fiber would make a nice project). There are some natural dyes that will work on cotton, however, especially if mordant with tannins. Among the better natural dyes for cotton are annato, cutch, logwood, madder, and indigo; all of these except for indigo require mordant's, while indigo requires a special type of dye vat.

Synthetic fibers usually cannot be dyed with natural dyes.

Types of dyes

There are three major types of natural dyes:

substantive dyes, which require no mordant

vat dyes

Mordant dyes, which require auxiliary substances to become attached to the fiber.

Less common forms of natural dyeing include rust dyeing, dye painting with earth oxides, and mud dyeing.

Substantive dyes are used by simply combining the dyestuff, usually in a quantity equal to or twice that of the weight of the fiber, with the fiber (or fabric) and simmering for an extended period of time. An example is turmeric, the spice, which works on cotton as well as on wool; others include onion skins, walnut husks, and tea. Substantive dyes, if made from edible materials, have the advantage of allowing the use of a regular cooking pot for dyeing in; most dyes, even natural dyes, and most mordant, require that a dye pot be devoted to their use, never to be used for cooking again. Another word for a substantive dye is direct; note that there are also a great many synthetic direct dyes.

Vat Dyes

The vat dyes work the same way on protein and cellulose, by being introduced into the surface of the fiber while in soluble form and then converted into an insoluble form. The vat dyes include many synthetic dyes, but also the natural dye indigo, and the ancient Tyrian Purple dye extracted from shellfish. They are complex to use, requiring the establishment of an anaerobic (oxygen-free) fermentation.

Mordant Dyes

Most natural dyeing is done with the use of mordant, most commonly heavy metal ions, but sometimes tannins. (Tannins are particularly important in dyeing cotton and other cellulose fibers.) The mordant allows many natural dyes which would otherwise just wash out to attain acceptable wash fastness. A mordant remains in the fiber permanently, holding the dye. Each different metal used as a mordant produces a different range of colors for each dye.

Why use natural dyes?

There are many reasons why people are turning to natural dyes even though synthetic dyes are more convenient to purchase and dye with. Each plant provides an amazing diversity of shades. From one plant you may obtain between 5-15 varying colours and shades. These colours and shades are subtle and tend to harmonize with one another. The resulting fabrics or fibers are now original pieces - it is extremely difficult for anyone to duplicate exactly (even the dyer).

Also there is the question of ecology. As people become more aware of environmental factors dyers are searching for alternatives. Natural dyes are seen as more eco-friendly as, unlike their synthetic counterparts, they are all derived from nature. The dye baths can be neutralized effectively through the addition of either acid or alkaline and then poured down the sink, or on to the garden. Use litmus paper to test the "pH", available at most chemists.

What are Mordants?

Mordant are metallic or mineral salts which, when added to the natural dye bath either enhance, intensify, or change the colour. They also play a large role in making the resulting shade faster to light and washing.

All mordants should be treated with care and common sense, but without panic. They need to be kept dry, away from sunlight, children, pets and food. Always wash hands before eating, drinking, smoking or using bathroom. Never use equipment that has been used in dyeing for cooking or food preparation. As a precaution it is a good idea to always add chemicals to water, not the other way around to avoid the solution spitting.

Generally all fibres are pre-mordanted with alum. This does not affect the colour of the dyestuff; it helps to increase wash and light fastness. Other mordants will alter the colour of the natural dye bath. Some dyers like to add mordants a pinch at a time until they see a colour change. Remember though that too much can damage your fibre.

Never put fibre in dye bath before mordants are added and dissolved. This protects fibres from exposure to high concentrations chemicals (which as noted before can deteriorate fibres).

Never put dry fibre in dye bath (to avoid uneven and streaky dyeing). It is a good idea to keep records of your own experiments in case you want to duplicate results.

All mordants can be made into solutions and stored. Dissolve in hot water, allow to cool, bottle and carefully label. Include the concentration, the date dissolved, and the use.

Dyers rarely agree on the quantities of mordant to be used. There are general guides though the best way for any dyer to find amount of mordant to be used is to conduct their own experiments.

Pre - Mordanting

This is done before dying. It results in even dyeing and fibres are quite fast to light and washing. Pre-mordanting of all yarns with Alum is quite common. Copper Sulphate can also be used. Fibres can also be successfully stored wet or dry after mordanting. If wet, fibre can be kept for a period of about 6 weeks providing it is well ventilated to prevent mold. If storing dry, fibre can be stored indefinitely.

Procedure

Soak wool for several hours to ensure complete saturation.

Fill enamel or stainless steel pot with enough water to cover your fibre.

Add dissolved mordant to dye pot.

Gently heat to room temperature and add wet fibre.

Slowly bring to a simmer and hold it there for an hour. DO NOT BOIL.

Stir occasionally, very gently and slowly.

Remove pot from heat and allow to cool overnight.

Remove fibre. It is now ready to be dyed or stored (wet or dry) for later use.

Mordants as additives

This is a process where you will be mordanting and dyeing at the same time, in the same dyebath. The benefit of this method is that the fibre is only processed once. This is ideal for fibres such as silk that deteriorate quickly in presence of strong chemicals. It is also good as it takes less time. One dye will yield several different shades or colours using this method. Keep careful records if ever you want to duplicate results.

Procedure

Prepare dyebath with selected dyestuff.

Divide into several pots.

Add mordants to dyepots a pinch at a time until you can see a visible colour change. (Amount will vary considerably for each mordant)

Add wet fibre to each.

Slowly raise the heat to simmering point and hold for an hour as above.

Allow to cool. Wash in small amount of pure soap.

Hang to dry in shade.

Using a pot as mordant

Aluminum, Iron, Copper, Tin and Brass pots will affect the colour of your dyebath. Instead of adding mordants, your pot simply replaces this need. This is a type of simultaneous dyeing. The dyeing procedure is the same, except you exclude mordants. Mordants can be added to pots, to give interesting results. This is generally only suitable for the dyer who does not want to control their colours.

Saddening and Blooming

Saddening and blooming is mordanting after the fibre has accepted the dye. This method is most widely used by experienced dyers who want to control the exact shade of their fibre. Generally ferrous sulphate is used to sadden colours and tin is used for brightening. One benefit of this method is that fibres are not exposed to chemicals for long periods of time, therefore not affecting the quality of the fibres.

Beverages

Today's beverage industry continues to grow and expand, offering consumers new product choices - and phosphates are key to the success of many new and rapidly growing beverage categories:

Isotonic drinks and sports beverages, high in cautions such as sodium and potassium, are designed specifically for consumption after exercise. Meal replacement drinks are nutritionally fortified beverages designed to serve as a complete meal. Soy beverages require phosphates to support dispersion of the soy protein and fortify the beverage with calcium minerals. Fruit-based beverages and teas benefit from phosphate ingredients.

Today's beverage industry continues to grow, and ICL food phosphates are key to the success of many new and rapidly growing beverage categories.

Soft Drinks

Phosphoric acid is used as an acidulant for cola and root beverages. Colas contain about 0.05% phosphoric acid and have a pH of about 2.3. Root beer has a higher pH of about 5.0 and contains 0.01% phosphoric acid. Despite the low use level, phosphoric acid is of extreme importance to beverage manufacturers. On a price performance basis, phosphoric acid is less expensive than organic acid alternatives. Phosphoric acid provides many advantages in the formulation by providing:

Sparkling bite and astringency counteract the heaviness of root and cola flavors.

Isotonic and Sports Drinks

These beverages are specifically formulated to replace fluids that are lost during exertion and to balance cations that will maintain or improve performance of the athlete.

Carbohydrates and water are the key ingredients in these drinks to replace energy and fluids. The other components are also important for their contribution to the osmolality, which is at a level similar to plasma. Orthophosphates are included in formulations for their contribution to the osmolality by their dissociation into ions. The Na+ and K+ ions are also important electrolytes in the body's metabolism. MSP and MKP are most often the phosphates of choice in isotonic beverages. The solubility and pH of these salts make them appropriate choices.

Juices

Beverages that contain fruit juice are common, popular drinks. They are gaining popularity in all segments of the population. Potassium, sodium, magnesium and calcium phosphates are added to fortify these drinks and utilize health claims as they are approved by the FDA. Tricalcium phosphate (TCP) can be added to low pH beverages such as fruit juices (which are opaque) as a source of calcium. The lack of interaction with other components minimizes impact on the flavor of the juice. Monopotassium phosphate (MKP), dipotassium phosphate (DKP), tripotassium phosphate (TKP), and tetrapotassium pyrophosphate (TKPP) are highly soluble phosphate salts that can be added to juice as a source of potassium. Glass HÂ® sodium hexametaphosphate (SHMP) is valuable to beverage manufacturers to increase shelf life. Cold-filled beverages with a low level of fruit juice can reduce the potassium sorbate and/or sodium benzoate levels by 50% (from 1000 to 500 ppm) with the addition of 0.1 to 0.15% (1000 to 1500 ppm) SHMP.This change in formulation results in reduced ingredient costs and improved flavor profile. SHMP also aids in color stabilization of fruit juice beverages or beverages containing fruit juice components.

Dairy Beverages

Dairy proteins and dairy components such as whey are frequently used in beverage products such as yogurt smoothies, milk-based sodas and whey-enhanced sports or protein drinks, as well as fluid milk itself. Proteins require protection, stabilization and dispersion in these systems. ICL phosphates are excellent tools to provide stable dairy-based beverages.

Fluid Milk Products

Sterilized milk, including ultra-high temperature (UHT) treated products, gains added storage life when stabilized with DSP or SHMP to prevent age gelation during storage. Powdered TSPP helps disperse and suspend cocoa and malted milk powder in milk. In addition, incorporating TSPP promotes formation of a thin gel layer around the milk proteins.

The gel enriches both the flavor, color and contributes to the smooth mouthfeel of the final beverage. Whey contains valuable protein and lactose, in dilute form. It is often used as a protein and energy source in beverages designed to enhance muscle development. Phosphates aid in whey processing as well as in stabilization, suspension and dispersion of whey protein in high performance beverages.

Soy Beverages

TSPP, SHMP, DSP and potassium phosphates can be used as stabilizing agents to help disperse soy proteins. Compared to cow's milk, soy milk contains only one-third the amount of calcium. TCP can be a good source of calcium fortification for soy milk and other soy products. Mag-nificentÂ® is an ideal source of magnesium in soybased beverages. It does not interact with the soy protein, minimizing undesirable odors and flavors.

Meal Replacement Drinks.

Monocalcium phosphate (MCP), dicalcium phosphate (DCP) and tricalcium phosphate (TCP) can be used as a source of calcium and phosphorus in beverages designed to be a complete meal. Mag-nificent is a source of magnesium and phosphorus. SHMP may also be used to aid in stabilizing the protein and solubilizing the mineral salts. In nutritionally fortified beverages, the metal complexing properties of polyphosphates (SHMP, STPP, TSPP) afford protection for vitamin C, which is readily oxidized in the presence of some metal ions. (See figure 3 on page 4 for phosphate metal complexing.) coffee Systems.

In coffee systems phosphates act to stabilize dairybased foams and non-dairy coffee whiteners. Foams of various compositions obtain increased aeration, or whipping efficiency, and foam stability from the addition of TSPP. By stabilizing the protein films, SHMP inhibits weeping, or drainage in milk-based foams, while DSP functions similarly in products based on other protein sources such as soybean.

ICL phosphates are effective at low levels to improve foam characteristics (see Figure 1). More air can be incorporated into foams made with dry milk; Glass HÂ® can double foam size, relative to the control. In non-dairy coffee whiteners, a phosphate buffering system consisting of DSP, DKP, SAPP and/or STPP contributes to stability of the protein layer around the fat droplets, thus preventing syneresis.

This buffer system also prevents feathering and fat separation when the coffee whitener is added to the hot acidic coffee medium. TSPP has also been used as a stabilizing agent to help disperse soy protein-based coffee whiteners.

Dry Mixes

H.T.Â® Monocalcium phosphate monohydrate (MCP) can be used in the formulation of beverage powders. MCP has many benefits:

Economical pH buffer to control tartness.

Nonhygroscopic acidulant replaces up to 50% of citric acid.

Calcium and phosphorus contribute to the products' nutrient profile. Tricalcium phosphate (TCP) is also commonly used for dry powder formulations where it contributes several useful properties:

Flow conditioning.

Clouding agent after reconstitution.

Benefits of Phosphates in Beverages

Flow Conditioning

TCP is generally utilized as a flow conditioner for powdered and fine granular products due to its small particle size, low electrical conductivity and ability to absorb water without becoming sticky. TCP is effective at levels of 0.5% to 3% as shown in Figure 2. When used in sugar, TCP has much better anti-caking effects than cornstarch.

TCP also contributes nutritional value. METAL COMPLEXING Metal complexing or sequestration is important in many beverage applications, see figure 3 for calcium sequestration. It is the interaction with calcium ions that lends itself to preservative enhancement. In nutritionally fortified beverages, the ability to complex calcium, magnesium and other minerals, and to stabilize them in a formulation, is key to delivering an acceptable product.

In dairy-based beverages, stabilization of proteins is often related to metal ion interaction. In carbonated beverages, chelation of troublesome metal ions helps establish a stable carbonation. The polyphosphates including NutrifosÂ® 088 STPP,

HexaphosÂ® SHMP and TSPP sequester metal cations, such as Ca2+, Mg2+, Fe2+ and Fe3+. Subsequently, this binding prevents the formation of undesirable precipitates or interactions. Sequestration of Ca2+ and Mg2+, present in water, sweeteners and other ingredients, helps to maintain beverage clarity and uniformity.

Preservative Enhancement

Long-chain polyphosphates, such as Glass H,can work synergistically with some preservatives in beverage systems. The mechanisms include: the chelation of metal ions in cell membranes; pH effect; increase in ionic strength; interactions with cell walls and membranes; and interference with various transport functions. The use of polyphosphates may lower the use level of preservatives.

Nutritional Enhancement

Calcium phosphates are broadly utilized in nutritional supplementation and fortification. They are a quality source of both calcium and phosphorus. Calcium is the most abundant mineral in the human body and is critical to the proper development of bone and teeth. Additionally, calcium is important in the prevention of osteoporosis, the promotion of normal growth and development of children, and participation in metabolic functions necessary for normal activity of nervous, muscular and skeletal systems.

The fine particle size of both DCP and TCP make them particularly useful in beverage applications, including some clear beverages. TCP and other calcium phosphates have a high level of calcium, when compared to other calcium products, which make them an efficient supplement (see Figure 4).

Magnesium is an essential mineral for physical health and well-being. Magnesium supports the formation of bone and teeth by assisting with the absorption of calcium and phosphorus. Mag-nificent is an ideal source of magnesium and phosphorus in one food ingredient for a number of beverage applications. It is compatible for use with calcium phosphates to balance the essential minerals.

Additionally, because Mag-nificent does not have a dramatic change in pH over time, it is compatible with other formulation components, including proteins and heat-sensitive vitamins. Figure 5 compares pH drift for Mag-nificent vs. magnesium oxide, another source of magnesium that is used in beverage applications.

Mag-nificent can be used in dairy-based beverages, meal replacement beverages, juices, waters and sports drinks to deliver magnesium, which is critical to cardiovascular health. Potassium phosphates have been recognized as key ingredients for supplementing products with potassium to achieve a "heart healthy" product claim.

Conclusion

We know have the knowledge and ability to understand about the chemicals used in making soaps, detergents, beverage, essential oils and natural dyes. Which seems to have some benefit associated with it, but may also have yet to be discovered problem associate with it. Because this not enough as the time has collapsed to allow scientist to study / look for any possible long term effects of all these chemicals used.

Different scientist comes up with different ideas and different chemicals so there are different things with similar name but with different chemicals. Scientist are still studying as which chemical is best for making soaps, detergent, essential oils etc.

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